Schedule II - Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands		12 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year		$ 1,258	$ 1,307	$ 1,501
Charged to costs and expenses		77,159	(3)	76
Charged to other accounts		0	0	0
Deductions		14	46	270
Balance at end of year		78,403	1,258	1,307
Allowance for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year		485	513	691
Charged to costs and expenses		516	(3)	76
Charged to other accounts		0	0	0
Deductions	[1]	14	25	254
Balance at end of year		987	485	513
Deferred tax valuation allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year		773	794	810
Charged to costs and expenses		76,643	0	0
Charged to other accounts		0	0	0
Deductions		0	21	16
Balance at end of year		$ 77,416	$ 773	$ 794

[1] Specific accounts written off as uncollectible.